Interior painting area – Exclude doors and windows: Room dimensions are 10 m × 7 m × 5 m (L × B × H). Two doors of 1 m × 3 m each, one window 2 m × 1.5 m, and two windows 1 m × 1.5 m each. Find the cost to paint the walls at Rs 3 per sq m.

Question

Solve this multiple-choice question and choose the correct option.

Curioustab · Accepted Answer

Introduction / Context:Interior wall painting area equals the total area of the four walls minus the area of openings (doors/windows). Then multiply by cost per square metre. Given Data / Assumptions: L = 10 m, B = 7 m, H = 5 m. Doors: 2 × (1 × 3) = 6 sq m. Windows: 1 × (2 × 1.5) = 3 sq m and 2 × (1 × 1.5) = 3 sq m ⇒ total windows = 6 sq m. Cost = Rs 3 per sq m. Concept / Approach:Wall area = perimeter * height. Paintable area = wall area − openings. Step-by-Step Solution: Perimeter = 2(L + B) = 2(10 + 7) = 34 m.Total wall area = 34 * 5 = 170 sq m.Openings area = 6 + 6 = 12 sq m.Paintable area = 170 − 12 = 158 sq m.Cost = 158 * 3 = Rs 474. Verification / Alternative check:Re-add doors/windows to ensure no omission: two doors (6), three windows (6) total 12 sq m ✔️ Why Other Options Are Wrong:174, 274, 374 result from subtracting wrong openings or using L + B instead of 2(L + B). Common Pitfalls:Accidentally including ceiling/floor; missing one window; not converting m to sq m properly. Final Answer:Rs.474

Interior painting area – Exclude doors and windows: Room dimensions are 10 m × 7 m × 5 m (L × B × H). Two doors of 1 m × 3 m each, one window 2 m × 1.5 m, and two windows 1 m × 1.5 m each. Find the cost to paint the walls at Rs 3 per sq m.

Answer

Explanation